Process of packaging batts of fibers



Nov. 3, 1970 M. D. LE VAN H L 3,537,226-

PROCESS OF PACKAGING BATTSQ OF FIBERS V Filed Oct. 27, 1967 BATT WRAPPED0N RIGID CORE,

REMOVING CORE AND. ENCASING ROLL IN AIR INPERVIDUS BAG.

INVENTOR.

MARTIN D. LE VAN ARNOLD L. WILLIS ATTORNEY United States Patent PROCESSOF PACKAGING BAITS OF FIBERS Martin D. Le Van, Wilmington, Del., andArnold L.

Willis, Chicago, 11].; said Martin D. Le Van assignor to E. I. du Pontde Nemours and Company, Wilmington, Del., a corporation of DelawareFiled Oct. 27, 1967, Ser. No. 678,745 Int. Cl. B65b 63/02, 63/04, 7/12US. C]. 53-24 1 Claim ABSTRACT OF THE DISCLOSURE The process ofpackaging initial batts of textile fibers at a density greater than theinitial batt density and without significant increase in initial battdensity upon unpackaging, which comprises:

(a) wrapping the initial batt onto a rigid core to form a cylindricalstructure;

(b) encasing the structure with a bag of an air impervious material andremoving the core;

(0) evacuating air from the bag to contract the structure and toincrease the initial batt density; and then (d) wrapping the contractedstructure with a Wrapper of sufiicient tensile strength to maintainsubstantially the contracted state.

BACKGROUND 'OF THE INVENTION Field of the invention This invention isconcerned with the handling of fiber batts. It is particularly concernedwith packaging fiber batts for shipment and storage. It is moreparticularly concerned with the vacuum packaging of batts in such a waythat higher density packages are formed without damage to the batts.

Description of the prior art Fiber batts are assemblies of fibers suchthat they form resilient masses suitable for use in pillows, mattresses,clothing insulation, furniture upholstery, and similar applications. Inorder that the batts serve these uses, it is essential that they have alarge proportion of open spaces and, hence, low densities. Due to thislow density, it is uneconomical to ship such batts. In the past suchbatts have been compressed, as disclosed in Barnett et al. US Pat.3,117,513 dated Ian. 14, 1964, to increase density, but this causes apermanent loss of some of the bulk and leaves creases and otherdistortions in the batts. Vacuum packaging of fibers is disclosed inBritish Pat. 1,017,164

(complete specification published Jan. 19, 1966). However, the processof this patent does not apply to batts of fibers and does not solve theproblem of packaging batts in the minimum space.

SUMMARY OF THE INVENTION In the present invention fiber batts are rolledup into cylindrical masses with a hollow center and these rolls areplaced in plastic bags. Air is evacuated from the bag and the rollassumes an oval cross-section. The bag is then sealed so that air cannotre-enter and the batt package maintains the oval cross-section shape dueto outside air pressure on the surface of the plastic bag. The battingis not appreciably creased and will expand to substantially its originalbulk when the bag is opened for use of the batting.

The invention is the process of packaging initial batts of textilefibers at a density of 2 to 4 times the initial batt density withoutsubstantial damage to the batt and without substantial increase ininitial batt density upon unpackaging, which comprises in its narrowerscope:

(a) wrapping the initial batt onto a rigid core to form a cylindricalstructure having a diameter within the range of about 20 to about 60inches, said core having a diameter within the range of about 10% to 35%of the cylindrical structure diameter;

(b) encasing the structure with a bag of an air impervious material andremoving the core;

(c) evacuating air from the bag to contact the structure to a density ofabout 2 to 4 times the initial batt density; and then (d) wrapping thecontracted structure with a wrapper of sufiicient tensile strength tomaintain substantially the contracted state.

DESCRIPTION OF THE DRAWING The drawing is a pictorial fiow chartillustrating the process of this invention. In the drawing, 1 representsthe open space within the interior of the batting. The rigid core isrepresented by 2, 3 depicts the fibers forming the batt, and 4 is theair impervious bag encasing the roll of batting.

DESCRIPTION OF THE PREFERRED EMBODIMENT Fiber battings are of maximumvalue on a Weight basis when they have maximum bulk-minimum density.However, since shipment of highly bulky materials is expensive, it isdesirable to increase the density of fiber batts for shipment. The highbulk should be easily restored after shipment if the batts are topossess maximum usefulness. The present invention achieves these resultsin a unique manner by winding the batts onto a cylindrical core,removing the core, placing the roll of batting in a plastic bag and thenevacuating the bag. When the core is removed the roll assumes an ovalcross-section. As the air is removed, the atmospheric pressure on theoutside of the bag causes a compression or contraction of the roll ofbatting to a greater density than the original batting. The evacuatedbag is sealed so that air cannot re-enter. When the bag is opened, aftershipment, the batting returns to near its original volume and originalbulk.

In a preferred manner of operating according to the present invention, abatting of 0.5 to 6 inches (1.3 to 15.2 cm.) thickness, 15 to inches(.38 to 2.16 meters) Width and 10 to 30 yards (9.15 to 27.4 meters) longconsisting of resin-treated polyester fibers is wound around a rigidtube having an outside diameter of 2 to 12 inches (5 to 30 cm.). Thetube core is removed from the roll and the roll placed in a polyethyleneor other plastic bag. The bag is evacuated to a pressure of about 2 to12 inches (5 to 30 cm.) of mercury. The bag is then sealed airtight,preferably wrapped with paper, and packed with other similar bags inshipping cartons. The paper wrapping maintains the compressed shape evenif air leaks into the plastic bag.

The density of the original batting is about 0.8 lb. per cubic foot(12.8 kilograms per stere) while the final packaged batting has adensity of about 2.4 lbs. per cubic foot (38.4 kilograms per stere).When the battings are removed from the bags they recover nearly all thebulk lost by packaging. The actual loss of bulk is usually less than 10%which is largely false bulk which would be lost during use of thebattings even without the vacuum packaging.

From the above density figures, it will be seen that the density can beincreased to three times or more its initial value for shipping. Thereduction in volume makes it possible to increase truck loads from 2,500lbs. (1133 kg.) to as high as 9,000 lbs. (4081 kg.). Greater densitiescan be obtained, but going beyond a density of 3 lbs. per cubic foot (48kg./stere) results in some permanent loss 9 u The g e t ns ty o herckess n tpnlre ds shipping but also makes storage more economical.

The size of the roll of batting may vary over rather wide limits, butbest results are obtained when the diameter of the batting rolls is 20to 60 inches, preferably 30 to 40 inches. When the core is removed, therolls become somewhat flattened and oval-shaped with a verticalthickness of about two-thirds 'thehorizontal thickness. In the preferredrange of operation, these dimen sions would be about 22 inches (56 cm.)for the vertical thickness and 35 inches (89 cm.) for the horizontalthickness. After evacuating, the vertical thickness is about 6 to inchesto 25 cm.) and the horizontal thickness is 25 to inches (63 to 89 cm.).j

No appreciable creasing .or crushingof the batts occurs under theoptimum conditions "for operating under this invention. Mechanicalcompression by the usual methods to give the same density'wouldseriously damage the batts.

Any natural or man-made-battings of fibers can be packaged by the methodof the present invention. -Most battings go into uses where highresilience is desirable, and for this reason, resilient fibers such asthe polyester fibers give optimum results. Even greater resilience isobtained when packaging resin-treated batts according to the presentinvention.

Fiber deniers are not critical for this process and may 4 qg (12.8 kiloa s Pe s ar te -4 pounds p cubic foot (38.4 kilograms per ster e).

The suction pipe is remoied from the bag, the end of the bag is twistedto form an air tight seal and the tightly twisted end is tucked into theroll to maintain the vacuum; The package is next wrapped in 60 basisweight paper (60 pounds per 3,000 square feet or 0.097 kilogram persquare meter) to protect the batt and to maintain the batt in itscontracted form in the event of air leakage.

This package can be shipped and stored much more cheaply than theoriginal batting. It occupies only onethird of the space occupied by theoriginal batting. When the wrapping is removed and the bag opened foruse, the batting immediately expands to approximately its originalvolume and is ready to be converted into upholsterypadding, cushions orthe like. .The batting is substantially free of wrinkles or distortion.A batting mechanically pressed to the same: small volume is badlycreased'and distorted and does not fully recover when the pressure isreleased. I

Since many different'embodiments of the invention may be made Withoutdeparting from the spirit and scope thereof, it is to be understood thatthe invention is not limited by the specific illustrations except to theextent vary from 1.5 denier to over 40 denier with values of 4 to 40denier preferred.

EXAMPLE I The resin is of the following composition:

' Percent:

Ethyl acrylate 46.3 Methyl methacrylate -2 48.0 N-methylolmethacrylamide4.7 Methacrylic acid 6 1.0

After spraying the surface another layer of fibersis crosslapped ontothe first layer, the surface is again sprayed and then the battingisturned over 'and the'opposite side is sprayed with the above r'esin.,Thefinal single batting is 1.1 inches (2.8 cm.) thick. The resin-treatedbatt is passed through an oven at 138C. to dry it and cure the resin.The batting contains about 15 resin on a .dry weight .basis.

This batting is next wrapped around a rigid tube type core having anoutside diameter of 10 inches (25.4 'cm.) until the diameterof therollis 40 inches. The core is then removed and the .roll'of batting partlycollapses to an oval cross-section. p

The roll is placed in a polyethylene bag having a wall thickness of 1.5mil (0.0038 cm.). A.2 inch (5.08 cm.) inside diameter" suction pipeisinserted into thejroll at the open end of the bag and the bag is tightlyfolded around this pipe to form an air tight seal. The air in the bag isremoved by applying a vacuum of 8 inches (20 cm.) of mercury to thepipe. The 10W pressure causes the bag and roll to collapsePThe rollcontracts to a flattened oval shape having a height of about 8 inches(20.3 cm.) and a width of abont.28 inches (71 cm.) in cross section. Atthe same time the density changes-from'0.8 pound per cubic defined inthe following claims. What is claimed is:

l. Inthe process of preparing a packaged resilient batt from. crimpedpolyethylene terephthalate fibers wherein the fibers in the form of websare assembled into a batt having a plurality of cross-lapped fiber layerand bonded to one another at cross-over points by applying a bonding aresin to form a low density batt suitable for use as padaged forshipment; the improvement for packaging the batt at an elevated densityin a manner that will allow the batt to resume a low density after beingremoved from the package and be substantially free of wrinkles anddistortion, wherein the improvement comprises wrapping thebatt around arigid core to form a roll, removing the core and collapsing the roll toan oval cross-section, plac- T ing the roll in a bag ofan-air-impervious material, evacuating the bag by applying a vacuum tocontract .the roll, twisting the 'open end of the bag and tucking itinto the collapsed roll to seal it, and wrapping the evacuated bag androll with paper to enclose and protect the rolled batt whereby the battis maintained at a density 2 to 4 times that of the original batt.

References Cited UNITED STATES PATENTS a US. 01. .R. 53-21, 22, 27, 37,370; 29 91.1

